Effects of Fire on Pines

Four yellow pine species native to the southern Appalachians show various degrees of adaptation to fire: Table Mountain pine, Virginia pine, shortleaf pine, and pitch pine. These four pine species are pioneers that require exposed mineral soil surfaces and full sunlight for their regeneration (USDA Forest Service 1965) and therefore, are not only resistant to fire, but require fire or other disturbance for their regeneration.

Table Mountain pine is one of the most fire-dependent pine species of the southern Appalachians. It requires moderate to high intensity surface and crown fires to open its serotinous cones (Zobel 1969, Barden 1978, Sanders 1992). Table Mountain pine is also very shade intolerant and therefore usually replaced by more shade-tolerant hardwoods, such as chestnut and scarlet oak, in the absence of fire (Williams and Johnson 1990, Williams and Johnson 1992, Sanders 1992). Individual Table Mountain pine trees may persist for up to 200 years without disturbance (Zobel 1969, Buckner and Turrill 1999).

Pitch pine also has several adaptations to fire, including a degree of cone serotiny (Fowells 1968), thick bark, dormant buds along the bole (Zobel 1969), and the development of a basal crook in seedlings that bring them into or against mineral soil on upland sites. Such buds often survive fires and produce new shoots (Little and Mergen 1966). Pitch pine grows in ecosystems that experience high-intensity fires at intervals of 10-30 years (Christensen 1981). Shortleaf pine also shows a degree of cone serotiny and develops a basal crook in seedlings (Little and Mergen 1966). Virginia pine has fewer specific adaptations to fire other than improved regeneration on burned sites. The fire-related adaptions of these pine species make fire an important silvicultural tool for stand development and maintenance (White and Lloyd 1997).